Reverend... sorry to break it to you, but the only way your car is leaning more with stiffer springs is that they are marked incorrectly or you were told that they are stiffer than they really are. Period. I recommend you take both sets of springs to have the rate tested. I can already tell you that your older springs were stiffer.

Your car is always 'pushing' down on your springs. Even when your car is at full lean, the inside springs are being pushed down by whatever percentage weight of your vehicle is on that particular corner. At some point, it may extend completely, and then the wheel will come off the ground.

I urge you to read some books on suspension tuning before continuing to post. We need to admit when we are in over our head and passing false information... I know you mean well and have good intentions. I'm not trying to flame you, I'm just saying read up before posting. I'm going to try to do some reading on this, too. I urge everyone out there to do some reading if you want to learn more about this.

 

Luis, springs were tested. I have the slips at home, but the were nearly dead on 5.1 kg/mm front 6.5 kg/mm rear, noticably stiffer ride, noticably more roll.

 

I'm not a suspension expert. I suppose I have a decent grasp of the underlying physics principles and when I see a claim that goes against them I always question it.

I find it hard to believe what you are claiming. But I also do not have any reason to believe that you may be making this up.

Many people make claims in this forum. From "I have just replaced my shiftknob and the car is now much quicker off the line" to decent, well documented claims. I have a general criticism and that is that most of the times people do not substantiate their claims. And we all know how a whole cluster of situations may lead one to alter one own's perceptions.

Anyway...

Maybe the stock shocks are being overpowered by the increased stiffness of your HKS springs, and are allowing faster load transfers. If this is the case you may have more body roll if transitions are sufficiently fast that the dampers do not allow full expansion/contraction on the stock springs but are doing so with the stiffer springs.

This however is a long shot (after all the spring rates are not that different and I doubt that Honda may mave cut short on shocks) and so I suspect that if you were to really measure body roll you'd find that the basic laws of physics still apply.

 

I would have said the same thing you guys are about springs and roll. But I gave it some thought after reading Reverend's post, and concluded that is it in fact possible to increase a cars roll with stiffer springs. Remember that there are different variables to account for but when the conditions are right, it can happen!

The simplest way to say it is that when the outside spring has stopped moving, and the inside spring still has room to move(before the wheel comes off the ground), cornering a lil bit harder will lift that side up. If they were softer springs that side wouldnt lift so easy.

Assuming your shocks are regular dampers, they are irrelevant when cornering at a steady rate. They mearly slow the springs down.

 

One last nail for the coffin of "stiffer springs = more body roll":

If you install stiffer and shorter springs (like I think rev did) you will experience less body roll not only as a result of the stiffer springs but also as a result of a lower chassis.

Shortening the springs lowers the centre of gravity of the car, so less weight transfer is generated for the same g-loads and thus less body roll.

 

Yes a lower center of gravity reduces roll but does not eliminate the 'more body roll' effect.

I suppose next you would say that a car with a 2" drop would NEVER flip over, huh.

Even if there is less potential for weight 'transfer', assuming you have the grip, you can roll a car right over.

Hmmm, if you can roll a car over, that means there is a heck of alot more force being applied to the car/ground than its original weight. That force is being applied to the outside, roll or not it will lower the force on the inside.
If the sus bottoms out, your roll point is now roughly your contact patch, making the inside not lighter but easier to lift. You know about levers right?

Bottoming out is an extreme case, but it's easiest to illustrate. The sus does not need to bottom out for this to happen.

[Edited by cmnsnse on 01-21-2001 at 09:39 AM]

 

Rev,
Are your HKS springs progressive? If so, my guess is that the "unloaded" side of the car is actually rising further than it was with the stock straight rate springs.

I've used progressive springs for short periods on a few of my old cars, and uniformly hated the way they performed. It felt like the car rolled more than it did w/the OE springs (experience w/GTI tuning, but may be somewhat relevant)

Just a thought/guess as to why you think the stiffer springs are rolling more...

Scott Stiles
'00 S2k
'00 S4
'01 GTI1.8t

 

Yeah, they are progressive at the top of the extension. They do that so that the spring will not unseat itself under hard cornering when one side becomes unloaded. The first couple coils are soft and very close together so that once you begin to load the spring at all, those compress together against each other almost immediately and you're left with a linear spring rate for the rest of your travel.

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Anyway, everyone, this thread has gotten out of hand and caused more trouble than it's worth. As many have pointed out , there is a lot of speculation here and not a lot of hard core backing for anything (this certainly INCLUDES MY POSTS). Anyway, at that, I'm locking the thread. If you have suspension questions, start a new thread and hopefully it will fare better than this one did.